TSH: 3.129 (.35-5.50)
T3: 2.9 (2.3-4.2)
T4, Free (Direct): 1.31 (.61-1.76)
Of course, my family doc who did the test said my numbers were fine. But he gave me the samples and said, if you really want to try it go ahead. Just let me know if you start having sweats, or your heart starts racing.
Classic hypo build:
I don't know that you have a classic hypo build. You dont look like you are carrying that much fat, particularly for your height and weight.
In any event, your TSH is somewhat elevated and many alternative docs would suggest that you are hypo and to get the TSH under 2.0. The Synthroid should accomplish that, and hopefully get the free T3 and T4 up. (Note, Jan's instructions pertain to Armour Thyroid, and if I were you, I would not be concerned about getting my free T3 to the top 25%.)
If I were you, I would start at 37.5 mcgs; that's what I started on, and my numbers were pretty similar to yours, though my TSH was lower.
If you get killer headaches or heart palps for more than a few days, stop and call your doc.
GL.